Table 1.
Baseline characteristic of osimertinib-treated patients evaluable for analysis of acquired resistance mechanisms
| Characteristic | AURA3 intent-to-treat population (n = 279)7 | Subset with valid NGS results* (n = 83) | Evaluable for resistance analysis subset (n = 78) |
|---|---|---|---|
| Median age (range), yr | 62 (25–85) | 61 (25–82) | 61 (25–82) |
| Female sex, no. (%) | 172 (62) | 49 (59) | 45 (58) |
| Race, no. (%)† | |||
| White | 89 (32) | 23 (28) | 23 (29) |
| Asian | 182 (65) | 59 (71) | 54 (69) |
| Other | 8 (3) | 1 (1) | 1 (1) |
| No history of smoking, no. (%) | 189 (68) | 56 (67) | 52 (67) |
| Disease classification, no. (%) | |||
| Adenocarcinoma histology not otherwise specified | 232 (83) | 69 (83) | 65 (83) |
| Metastatic disease | 266 (95) | 81 (98) | 76 (97) |
| CNS metastases‡ | 93 (33) | 27 (33) | 26 (33) |
| Extrathoratic visceral metastases | 145 (52) | 50 (60) | 47 (60) |
| EGFR mutation type | |||
| T790M | 275 (99) | 82 (99) | 77 (99) |
| L858R | 83 (30) | 23 (28) | 20 (26) |
| G719X | 4 (1) | 1 (1) | 1 (1) |
| S768I | 1 (<1) | 0 | 0 |
| Exon 19 deletion | 191 (68) | 59 (71) | 57 (73) |
| Exon 20 insertion | 1 (<1) | 0 | 0 |
| Previous EGFR-TKI therapy | |||
| Gefitinib | 166 (59) | 44 (53) | 39 (50) |
| Erlotinib | 96 (34) | 34 (41) | 34 (44) |
| Afatinib | 20 (7) | 6 (7) | 6 (8) |
*Patients with paired plasma samples that had valid NGS results at baseline and at the time of disease progression or treatment discontinuation.
†Race was self-reported. The category of “other” includes black, American Indian, and Alaska Native
‡CNS metastases were determined programmatically from baseline data of CNS lesion site, medical history, and/or surgery, and/or radiotherapy. The patient was identified as having a locally advanced disease in the brain.
CNS central nervous system, EGFR-TKI epidermal growth factor receptor tyrosine kinase inhibitor, NGS next-generation sequencing, WHO World Health Organization.